Light emitting panel assemblies

ABSTRACT

Light emitting assemblies include at least one light source and at least one film, sheet, plate or substrate having optical elements or deformities of well defined shape on at least one surface that have reflective or refractive surfaces for controlling the light output ray angle distribution of the emitted light. The film, sheet, plate or substrate may be positioned near the light emitting surface of a light emitting panel member with an air gap therebetween or over a cavity or recess in a tray through which light from a light source in the cavity or recess is emitted.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. patent application Ser. No.10/784,527, filed Feb. 23, 2004, which is a division of U.S. patentapplication Ser. No. 09/256,275, filed Feb. 23, 1999, now U.S. Pat. No.6,712,481, dated Mar. 30, 2004, which is a continuation-in-part of U.S.patent application Ser. No. 08/778,089, filed Jan. 2, 1997, now U.S.Pat. No. 6,079,838, dated Jun. 27, 2000, which is a division of U.S.patent application Ser. No. 08/495,176, filed Jun. 27, 1995, now U.S.Pat. No. 5,613,751, dated Mar. 25, 1997.

BACKGROUND OF THE INVENTION

This invention relates generally, as indicated, to light emitting panelassemblies each including a transparent panel member for efficientlyconducting light, and controlling the light conducted by the panelmember to be emitted from one or more light output areas along thelength thereof.

Light emitting panel assemblies are generally known. However, thepresent invention relates to several different light emitting panelassembly configurations which provide for better control of the lightoutput from the panel assemblies and for more efficient utilization oflight, which results in greater light output from the panel assemblies.

SUMMARY OF THE INVENTION

In accordance with one aspect of the invention, the light emitting panelassemblies include a light emitting panel member having a lighttransition area in which at least one light source is suitably mountedfor transmission of light to the light input surface of the panelmember.

In accordance with another aspect of the invention, the light source isdesirably embedded, potted or bonded to the light transition area toeliminate any air gaps, decrease surface reflections and/or eliminateany lens effect between the light source and light transition area,thereby reducing light loss and increasing the light output from thepanel assembly.

In accordance with another aspect of the invention, the panel assembliesmay include reflective or refractive surfaces for changing the path of aportion of the light, emitted from the light source, that would notnormally enter the panel members at an acceptable angle that allows thelight to remain in the panel members for a longer period of time and/orincrease the efficiency of the panel members.

In accordance with another aspect of the invention, the light emittingpanel members include a pattern of light extracting deformities ordisruptions which provide a desired light output distribution from thepanel members by changing the angle of refraction of a portion of thelight from one or more light output areas of the panel members.

In accordance with still another aspect of the invention, the lightsource may include multiple colored light sources for supplying light toone or more light output areas, and for providing a colored or whitelight output distribution.

In accordance with yet another aspect of the invention, the panelassemblies include a transition area for mixing the multiple coloredlights, prior to the light entering the panel members, in order toeffect a desired colored or white light output distribution.

The various light emitting panel assemblies of the present invention arevery efficient panel assemblies that may be used to produce increaseduniformity and higher light output from the panel members with lowerpower requirements, and allow the panel members to be made thinnerand/or longer, and/or of various shapes and sizes.

To the accomplishment of the foregoing and related ends, the inventionthen comprises the features hereinafter fully described and particularlypointed out in the claims, the following description and the annexeddrawings setting forth in detail certain illustrative embodiments of theinvention, these being indicative, however, of but several of thevarious ways in which the principles of the invention may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

In the annexed drawings:

FIGS. 1 through 3 are schematic perspective views of three differentforms of light emitting panel assemblies in accordance with thisinvention;

FIG. 4 a is an enlarged plan view of a portion of a light output area ofa panel assembly showing one form of pattern of light extractingdeformities on the light output area;

FIGS. 4 b, c and d are enlarged schematic perspective views of a portionof a light output area of a panel assembly showing other forms of lightextracting deformities formed in or on the light output area;

FIG. 5 is an enlarged transverse section through the light emittingpanel assembly of FIG. 3 taken generally on the plane of the line 5-5thereof;

FIG. 6 is a schematic perspective view of another form of light emittingpanel assembly in accordance with this invention;

FIG. 7 is a schematic top plan view of another form of light emittingpanel assembly in accordance with this invention;

FIG. 8 is a schematic perspective view of another form of light emittingpanel assembly in accordance with this invention;

FIG. 9 is a schematic top plan view of another form of light emittingpanel assembly in accordance with this invention;

FIG. 10 is a schematic top plan view of still another form of lightemitting panel assembly in accordance with this invention;

FIG. 11 is a side elevation view of the light emitting panel assembly ofFIG. 10;

FIG. 11 a is a fragmentary side elevation view showing a tapered orrounded end on the panel member in place of the prismatic surface shownin FIGS. 10 and 11;

FIG. 12 is a schematic top plan view of another form of light emittingpanel assembly in accordance with this invention;

FIG. 13 is a schematic side elevation view of the light emitting panelassembly of FIG. 12; and

FIGS. 14 and 15 are schematic perspective views of still other forms oflight emitting panel assemblies in accordance with this invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now in detail to the drawings, and initially to FIG. 1, thereis schematically shown one form of light emitting panel assembly 1 inaccordance with this invention including a transparent light emittingpanel 2 and one or more light sources 3 which emit light in apredetermined pattern in a light transition member or area 4 used tomake the transition from the light source 3 to the light emitting panel2, as well known in the art. The light that is transmitted by the lighttransition area 4 to the transparent light emitting panel 2 may beemitted along the entire length of the panel or from one or more lightoutput areas along the length of the panel as desired to produce adesired light output distribution to fit a particular application.

In FIG. 1 the light transition area 4 is shown as an integral extensionof one end of the light emitting panel 2 and as being generallyrectangular in shape. However, the light transition area may be of othershapes suitable for embedding, potting, bonding or otherwise mountingthe light source. Also, reflective or refractive surfaces may beprovided to increase efficiency. Moreover, the light transition area 4may be a separate piece suitably attached to the light input surface 13of the panel member if desired. Also, the sides of the light transitionarea may be curved to more efficiently reflect or refract a portion ofthe light emitted from the light source through the light emitting panelat an acceptable angle.

FIG. 2 shows another form of light emitting panel assembly 5 inaccordance with this invention including a panel light transition area 6at one end of the light emitting panel 7 with sides 8, 9 around andbehind the light source 3 shaped to more efficiently reflect and/orrefract and focus the light emitted from the light source 3 thatimpinges on these surfaces back through the light transition area 6 atan acceptable angle for entering the light input surface 18 at one endof the light emitting panel 7. Also, a suitable reflective material orcoating 10 may be provided on the portions of the sides of the lighttransition areas of the panel assemblies of FIGS. 1 and 2 on which aportion of the light impinges for maximizing the amount of light orotherwise changing the light that is reflected back through the lighttransition areas and into the light emitting panels.

The panel assemblies shown in FIGS. 1 and 2 include a single lightsource 3, whereas FIG. 3 shows another light emitting panel assembly 11in accordance with this invention including two light sources 3. Ofcourse, it will be appreciated that the panel assemblies of the presentinvention may be provided with any number of light sources as desired,depending on the particular application.

The panel assembly 11 of FIG. 3 includes a light transition area 12 atone end of the light emitting panel 14 having reflective and/orrefractive surfaces 15 around and behind each light source 3. Thesesurfaces 15 may be appropriately shaped including for example curved,straight and/or faceted surfaces, and if desired, suitable reflectivematerials or coatings may be provided on portions of these surfaces tomore efficiently reflect and/or refract and focus a portion of the lightemitted for example from an incandescent light source which emits lightin a 3600 pattern through the light transition areas 12 into the lightinput surface 19 of the light emitting panel 14.

The light sources 3 may be mechanically held in any suitable manner inslots, cavities or openings 16 machined, molded or otherwise formed inthe light transition areas of the panel assemblies. However, preferablythe light sources 3 are embedded, potted or bonded in the lighttransition areas in order to eliminate any air gaps or air interfacesurfaces between the light sources and surrounding light transitionareas, thereby reducing light loss and increasing the light outputemitted by the light emitting panels. Such mounting of the light sourcesmay be accomplished, for example, by bonding the light sources 3 in theslots, cavities or openings 16 in the light transition areas using asufficient quantity of a suitable embedding, potting or bonding material17. The slots, cavities or openings 16 may be on the top, bottom, sidesor back of the light transition areas. Bonding can also be accomplishedby a variety of methods that do not incorporate extra material, forexample, thermal bonding, heat staking, ultrasonic or plastic welding orthe like. Other methods of bonding include insert molding and castingaround the light source(s).

A transparent light emitting material of any suitable type, for exampleacrylic or polycarbonate, may be used for the light emitting panels.Also, the panels may be substantially flat, or curved, may be a singlelayer or multi-layers, and may have different thicknesses and shapes.Moreover, the panels may be flexible, or rigid, and may be made out of avariety of compounds. Further, the panels may be hollow, filled withliquid, air, or be solid, and may have holes or ridges in the panels.

Each light source 3 may also be of any suitable type including, forexample, any of the types disclosed in U.S. Pat. Nos. 4,897,771 and5,005,108,assigned to the same assignee as the present application, theentire disclosures of which are incorporated herein by reference. Inparticular, the light sources 3 may be an arc lamp, an incandescent bulbwhich also may be colored, filtered or painted, a lens end bulb, a linelight, a halogen lamp, a light emitting diode (LED), a chip from an LED,a neon bulb, a fluorescent tube, a fiber optic light pipe transmittingfrom a remote source, a laser or laser diode, or any other suitablelight source. Additionally, the light sources 3 may be a multiplecolored LED, or a combination of multiple colored radiation sources inorder to provide a desired colored or white light output distribution.For example, a plurality of colored lights such as LEDs of differentcolors (red, blue, green) or a single LED with multiple colored chipsmay be employed to create white light or any other colored light outputdistribution by varying the intensities of each individual coloredlight.

A pattern of light extracting deformities or disruptions may be providedon one or both sides of the panel members or on one or more selectedareas on one or both sides of the panel members, as desired. FIG. 4 aschematically shows one such light surface area 20 on which a pattern oflight extracting deformities or disruptions 21 is provided. As usedherein, the term deformities or disruptions are used interchangeably tomean any change in the shape or geometry of the panel surface and/orcoating or surface treatment that causes a portion of the light to beemitted. The pattern of light extracting deformities 21 shown in FIG. 4a includes a variable pattern which breaks up the light rays such thatthe internal angle of reflection of a portion of the light rays will begreat enough to cause the light rays either to be emitted out of thepanel through the side or sides on which the light extractingdeformities 21 are provided or reflected back through the panel andemitted out the other side.

These deformities or disruptions 21 can be produced in a variety ofmanners, for example, by providing a painted pattern, an etched pattern,a machined pattern, a printed pattern, a hot stamped pattern, or amolded pattern or the like on selected light output areas of the panelmembers. An ink or printed pattern may be applied for example by padprinting, silk screening, ink jet, heat transfer film process or thelike. The deformities may also be printed on a sheet or film which isused to apply the deformities to the panel member. This sheet or filmmay become a permanent part of the light panel assembly for example byattaching or otherwise positioning the sheet or film against one or bothsides of the panel member similar to the sheet or film 27 shown in FIGS.3 and 5 in order to produce a desired effect.

By varying the density, opaqueness or translucence, shape, depth, color,area, index of refraction, or type of deformities 21 on an area or areasof the panels, the light output of the panels can be controlled. Thedeformities or disruptions may be used to control the percent of lightemitted from any area of the panels. For example, less and/or smallersize deformities 21 may be placed on panel areas where less light outputis wanted. Conversely, a greater percentage of and/or larger deformitiesmay be placed on areas of the panels where greater light output isdesired.

Varying the percentages and/or size of deformities in different areas ofthe panel is necessary in order to provide a uniform light outputdistribution. For example, the amount of light traveling through thepanels will ordinarily be greater in areas closer to the light sourcethan in other areas further removed from the light source. A pattern oflight extracting deformities 21 may be used to adjust for the lightvariances within the panel members, for example, by providing a denserconcentration of light extracting deformities with increased distancefrom the light source 3 thereby resulting in a more uniform light outputdistribution from the light emitting panels.

The deformities 21 may also be used to control the output ray angledistribution of the emitted light to suit a particular application. Forexample, if the panel assemblies are used to provide a liquid crystaldisplay backlight, the light output will be more efficient if thedeformities 21 cause the light rays to emit from the panels atpredetermined ray angles such that they will pass through the liquidcrystal display with low loss.

Additionally, the pattern of light extracting deformities may be used toadjust for light output variances attributed to light extractions of thepanel members. The pattern of light extracting deformities 21 may beprinted on the light output areas utilizing a wide spectrum of paints,inks, coatings, epoxies, or the like, ranging from glossy to opaque orboth, and may employ half-tone separation techniques to vary thedeformity 21 coverage. Moreover, the pattern of light extractingdeformities 21 may be multiple layers or vary in index of refraction.

Print patterns of light extracting deformities 21 may vary in shapessuch as dots, squares, diamonds, ellipses, stars, random shapes, and thelike, and are desirably 0.006 square inch per deformity/element or less.Also, print patterns that are 60 lines per inch or finer are desirablyemployed, thus making the deformities or shapes 21 in the print patternsnearly invisible to the human eye in a particular application therebyeliminating the detection of gradient or banding lines that are commonto light extracting patterns utilizing larger elements. Additionally,the deformities may vary in shape and/or size along the length and/orwidth of the panel members. Also, a random placement pattern of thedeformities may be utilized throughout the length and/or width of thepanel members. The deformities may have shapes or a pattern with nospecific angles to reduce moiré or other interference effects. Examplesof methods to create these random patterns are printing a pattern ofshapes using stochastic print pattern techniques, frequency modulatedhalf tone patterns, or random dot half tones. Moreover, the deformitiesmay be colored in order to effect color correction in the panel members.The color of the deformities may also vary throughout the panel members,for example to provide different colors for the same or different lightoutput areas.

In addition to or in lieu of the patterns of light extractingdeformities 21 shown in FIG. 4 a, other light extracting deformitiesincluding prismatic surfaces, depressions or raised surfaces of variousshapes using more complex shapes in a mold pattern may be molded,etched, stamped, thermoformed, hot stamped or the like into or on one ormore areas of the panel member. FIGS. 4 b and 4 c show panel areas 22 onwhich prismatic surfaces 23 or depressions 24 are formed in the panelareas, whereas FIG. 4 d shows prismatic or other reflective orrefractive surfaces 25 formed on the exterior of the panel area. Theprismatic surfaces, depressions or raised surfaces will cause a portionof the light rays contacted thereby to be emitted from the panel member.Also, the angles of the prisms, depressions or other surfaces may bevaried to direct the light in different directions to produce a desiredlight output distribution or effect. Moreover, the reflective orrefractive surfaces may have shapes or a pattern with no specific anglesto reduce moiré or other interference effects.

As best seen in the cross sectional view of FIG. 5, a back reflector(including trans reflectors) 26 may be attached or positioned againstone side of the panel member 14 of FIG. 3 using a suitable adhesive 28or other method in order to improve light output efficiency of the panelassembly 11 by reflecting the light emitted from that side back throughthe panel for emission through the opposite side. Additionally, apattern of light extracting deformities 21, 23, 24 and/or 25 may beprovided on one or both sides of the panel member in order to change thepath of the light so that the internal critical angle is exceeded and aportion of the light is emitted from one or both sides of the panel.Moreover, a transparent film, sheet or plate 27 may be attached orpositioned against the side or sides of the panel member from whichlight is emitted using a suitable adhesive 28 or other method in orderto produce a desired effect.

The member 27 may be used to further improve the uniformity of the lightoutput distribution. For example, the member 27 may be a colored film, adiffuser, or a label or display, a portion of which may be a transparentoverlay that may be colored and/or have text or an image thereon.

If adhesive 28 is used to adhere the back reflector 26 and/or film 27 tothe panel, the adhesive is preferably applied only along the side edgesof the panel, and if desired the end edge opposite the light transitionareas 12, but not over the entire surface area or areas of the panelbecause of the difficulty in consistently applying a uniform coating ofadhesive to the panel. Also, the adhesive changes the internal criticalangle of the light in a less controllable manner than the air gaps 30(see FIG. 5) which are formed between the respective panel surfaces andthe back reflector 26 and/or film 27 when only adhered along theperipheral edges. Additionally, longer panel members are achievable whenair gaps 30 are used. If adhesive were to be used over the entiresurface, the pattern of deformities could be adjusted to account for theadditional attenuation in the light caused by the adhesive.

Referring further to FIG. 2, the panel assembly 5 shown therein alsoincludes molded posts 31 at one or more corners of the panel 7 (foursuch posts being shown) which may be used to facilitate mounting of thepanel assembly and providing structural support for other parts orcomponents, for example, a display panel such as a liquid crystaldisplay panel as desired.

FIG. 6 shows another form of light emitting panel assembly 32 inaccordance with this invention including a panel member 33, one or morelight sources 3, and one or more light output areas 34. In addition, thepanel assembly 32 includes a tray 35 having a cavity or recess 36 inwhich the panel assembly 32 is received. The tray 35 may act as a backreflector as well as end edge and/or side edge reflectors for the panel33 and side and/or back reflectors 37 for the light sources 3.Additionally, one or more secondary reflective or refractive surfaces 38may be provided on the panel member 33 and/or tray 35 to reflect aportion of the light around one or more corners or curves in anon-rectangular shaped panel member 33. These secondaryreflective/refractive surfaces 38 may be flat, angled, faceted orcurved, and may be used to extract a portion of the light away from thepanel member in a predetermined pattern. FIG. 6 also shows multiplelight output areas 34 on the panel member that emit light from one ormore light sources 3.

FIG. 7 is a schematic illustration of still another form of lightemitting panel assembly 40 in accordance with this invention including apanel member 41 having one or more light output areas 42 and one or morelight transition areas (mixing areas) 43 containing a plurality of lightsources 3 at one or both ends of the panel. Each transition area mixesthe light from one or more light sources having different colors and/orintensities. In this particular embodiment, each of the light sources 3desirably employs three colored LEDs (red, blue, green) in eachtransition mixing area 43 so that the light from the three LEDs can bemixed to produce a desired light output color that will be emitted fromthe light output area 42. Alternatively, each light source may be asingle LED having multiple colored chips bonded to the lead film. Also,two colored LEDs or a single LED having two colored chips may be usedfor a particular application. By varying the intensities of theindividual respective LEDs, virtually any colored light output or whitelight distribution can be achieved.

FIG. 8 shows yet another form of light emitting panel assembly 45 inaccordance with this invention including a light emitting panel member46 and a light source 3 in a light transition area 48 integral with oneend of the panel member. In this particular embodiment, the panel member46 is three-dimensionally curved, for example, such that light rays maybe emitted in a manner that facilitates aesthetic design of a lighteddisplay.

FIG. 9 schematically shows another form of light emitting panel assembly50 in accordance with this invention, including a panel member 51 havingmultiple light output areas 52, and mounting posts and/or mounting tabs53. This particular panel assembly 50 may serve as a structural memberto support other parts or components as by providing holes or cavities54, 55 in the panel member 51 which allow for the insertion of modularcomponents or other parts into the panel member. Moreover, a separatecavity or recess 56 may be provided in the panel member 51 for receiptof a correspondingly shaped light transition area 57 having one or morelight sources 3 embedded, bonded, cast, insert molded, epoxied, orotherwise mounted or positioned therein and a curved reflective orrefractive surface 58 on the transition area 57 and/or wall of thecavity or recess 56 to redirect a portion of the light in apredetermined manner. In this way the light transition area 57 and/orpanel member may be in the form of a separate insert which facilitatesthe easy placement of the light source in a modular manner. A reflector58 may be placed on the reflective or refractive surface of the cavityor recess 56 or insert 57. Where the reflector 58 is placed on thereflective or refractive surface of the cavity or recess 56, the cavityor recess may act as a mold permitting transparent material from whichthe transition area 57 is made to be cast around one or more lightsources 3.

FIGS. 10 and 11 schematically show another form of light emitting panelassembly 60 in accordance with this invention including a panel member61 having one or more light output areas 62. In this particularembodiment, an off-axis light transition area 63 is provided that isthicker in cross section than the panel member to permit use of one ormore light sources 3 embedded or otherwise mounted in the lighttransition area that are dimensionally thicker than the panel member.Also, a three-dimensional reflective surface 64 (FIG. 11) may beprovided on the transition area 63. Moreover, a prism 65 (FIG. 11) ortapered, rounded, or otherwise shaped end 66 (FIG. 11 a) may be providedat the end of the panel opposite the light sources 3 to perform thefunction of an end reflector. The light sources 3 may be oriented atdifferent angles relative to each other and offset to facilitate bettermixing of the light rays 67 in the transition area 63 as schematicallyshown in FIG. 10 and/or to permit a shorter length transition area 63 tobe used.

FIGS. 12 and 13 schematically show still another form of light emittingpanel assembly 70 in accordance with this invention which includes oneor more light transition areas 71 at one or both ends of the panelmember 72 each containing a single light source 73. The transition areaor areas 71 shown in FIGS. 12 and 13 collect light with multiple orthree-dimensional surfaces and/or collect light in more than one plane.For example each transition area 71 shown in FIGS. 12 and 13 haselliptical and parabolic shape surfaces 74 and 75 in different planesfor directing the light rays 76 into the panel member at a desiredangle.

Providing one or more transition areas at one or both ends of the panelmember of any desired dimension to accommodate one or more lightsources, with reflective and/or refractive surfaces on the transitionareas for redirecting the light rays into the panel member at relativelylow angles allows the light emitting panel member to be made much longerand thinner than would otherwise be possible. For example the panelmembers of the present invention may be made very thin, i.e., 0.125 inchthick or less.

FIG. 14 schematically illustrates still another form of light emittingpanel assembly 80 in accordance with this invention including a lightemitting panel 81 and one or more light sources 3 positioned, embedded,potted, bonded or otherwise mounted in a light transition area 82 thatis at an angle relative to the panel member 81 to permit more efficientuse of space. An angled or curved reflective or refractive surface 83 isprovided at the junction of the panel member 81 with the transition area82 in order to reflect/refract light from the light source 3 into thebody of the panel member 81 for emission of light from one or more lightemitting areas 84 along the length of the panel member.

FIG. 15 schematically illustrates still another form of light emittingpanel assembly 90 in accordance with this invention including a lighttransition area 91 at one or both ends of a light emitting panel member92 containing a slot 93 for sliding receipt of an LED or other suitablelight source 3. Preferably the slot 93 extends into the transition area91 from the back edge 94, whereby the light source 3 may be slid and/orsnapped in place in the slot from the back, thus allowing the transitionarea to be made shorter and/or thinner. The light source 3 may beprovided with wings, tabs or other surfaces 95 for engagement incorrespondingly shaped recesses or grooves 96 or the like in thetransition area 91 for locating and, if desired, securing the lightsource in place. Also, the light source 3 may be embedded, potted,bonded or otherwise secured within the slot 93 in the light transitionarea 91 of the panel member 92. Light from a secondary light source 97may be projected through the panel member 92 for indication or someother effect.

The various light emitting panel assemblies disclosed herein may be usedfor a great many different applications including for example LCD backlighting or lighting in general, decorative and display lighting,automotive lighting, dental lighting, phototherapy or other medicallighting, membrane switch lighting, and sporting goods and apparellighting or the like. Also the panel assemblies may be made such thatthe panel members and deformities are transparent without a backreflector. This allows the panel assemblies to be used for example tofront light an LCD or other display such that the display is viewedthrough the transparent panel members.

Although the invention has been shown and described with respect tocertain preferred embodiments, it is obvious that equivalent alterationsand modifications will occur to others skilled in the art upon thereading and understanding of the specification. The present inventionincludes all such equivalent alterations and modifications, and islimited only by the scope of the claims.

1. A light emitting assembly comprising at least a light emitting panelmember having a light emitting surface, at least one light source, atleast one film, sheet, plate or substrate positioned near the lightemitting surface through which light from the panel member is emitted,and an air gap between the film, sheet, plate or substrate and the panelmember, wherein at least one surface of the film, sheet, plate orsubstrate has one or more reflective or refractive surfaces, and atleast one of the reflective or refractive surfaces has well definedoptical elements or deformities for controlling the emitted light suchthat at least some of the light is redirected to pass through a liquidcrystal display with low loss.
 2. The assembly of claim 1 wherein atleast some of the reflective surfaces or deformities have a reflectivematerial or coating.
 3. The assembly of claim 1 wherein at least some ofthe reflective or refractive surfaces are shaped or patterned to reducemoiré or other interference effects.
 4. The assembly of claim 1 whereinlight from at least two light sources partially mixes in at least aportion of the light emitting assembly.
 5. The assembly of claim 4wherein the portion of the light emitting assembly in which the lightpartially mixes is the panel member.
 6. The assembly of claim 4 whereinthe portion of the light emitting assembly in which the light partiallymixes is the air gap.
 7. The assembly of claim 4 wherein two or more ofthe light sources are different colored light sources.
 8. The assemblyof claim 4 wherein two or more of the light sources are differentcolored LEDs.
 9. The assembly of claim 1 wherein at least one lightsource is a single LED with multicolored chips.
 10. The assembly ofclaim 1 further comprising a tray that holds or positions the film,sheet, plate or substrate relative to one or more light sources.
 11. Theassembly of claim 1 wherein an additional film, sheet, plate orsubstrate is positioned near the one film, sheet, plate or substrate toredirect at least a portion of the emitted light to produce a desiredlight output distribution or effect.
 12. The assembly of claim 11wherein there is an additional air gap between the one film, sheet,plate or substrate and the additional film, sheet, plate or substrate.13. The assembly of claim 11 wherein the additional film, sheet, plateor substrate has prismatic or lenticular surfaces.
 14. The assembly ofclaim 11 wherein the additional film, sheet, plate or substrate hasoptical elements that are quite small relative to the length and widthof the additional film, sheet, plate or substrate.
 15. The assembly ofclaim 11 wherein the additional film, sheet, plate or substrate is adiffuser or brightness enhancement film.
 16. A light emitting assemblycomprising at least a tray that forms a cavity or recess, at least onelight source positioned within the cavity or recess, at least one film,sheet, plate or substrate positioned over the cavity or recess throughwhich light from the light source is emitted, wherein at least onesurface of the film, sheet, plate or substrate has one or morereflective or refractive surfaces, and at least one of the reflective orrefractive surfaces has well defined optical elements or deformities forcontrolling the emitted light such that at least some of the light isredirected to pass through a liquid crystal display with low loss. 17.The assembly of claim 16 wherein the tray acts as a back reflector, anend edge reflector and/or a side edge reflector.
 18. The assembly ofclaim 16 wherein light from at least two light sources partially mixesin at least a portion of the light emitting assembly.
 19. The assemblyof claim 18 wherein two or more of the light sources are differentcolored light sources.
 20. The assembly of claim 18 wherein two or moreof the light sources are different colored LEDs.
 21. The assembly ofclaim 16 wherein at least one light source is a single LED withmulticolored chips.
 22. The assembly of claim 16 wherein the tray holdsor positions the one film, sheet, plate or substrate relative to the oneor more light sources.
 23. The assembly of claim 16 wherein anadditional transparent film, sheet, plate or substrate is positionednear the one film, sheet, plate or substrate to redirect at least aportion of the emitted light to produce a desired light outputdistribution or effect.
 24. The assembly of claim 23 wherein there is anair gap between the one film, sheet, plate or substrate and theadditional film, sheet, plate or substrate.
 25. The assembly of claim 23wherein the additional film, sheet, plate or substrate has prismatic orlenticular surfaces.
 26. The assembly of claim 23 wherein the additionalfilm, sheet, plate or substrate has optical elements that are quitesmall relative to the length and width of the additional film, sheet,plate or substrate.
 27. The assembly of claim 23 wherein the additionalfilm, sheet, plate or substrate is a diffuser or brightness enhancementfilm.
 28. A light emitting assembly comprising at least one light sourceand at least one transparent film, sheet, plate or substrate having topand bottom surfaces, a plurality of optical elements or deformities ofwell defined shape on or in the top and bottom surfaces, at least someof the optical elements or deformities on or in at least one of the topand bottom surfaces having one or more reflective or refractive surfacesfor controlling the emitted light such that at least some of the lightis redirected to pass through a liquid crystal display with low loss.29. The assembly of claim 28 wherein the optical elements or deformitieson or in the top surface of the film, sheet, plate or substrate aredifferent than the optical elements or deformities on or in the bottomsurface.
 30. The assembly of claim 28 wherein at least some of theoptical elements or deformities are multiple layers or vary in index ofrefraction.
 31. A light emitting assembly comprising at least a lightemitting panel member having a light emitting surface, at least onelight source, at least one film, sheet, plate or substrate positionednear the light emitting surface through which light from the panelmember is emitted, and an air gap between the film, sheet, plate orsubstrate and the panel member, wherein at least one surface of thefilm, sheet, plate or substrate has one or more reflective or refractivesurfaces that are well defined optical elements or deformities forcontrolling the light output ray angle distribution of the emitted lightto suit a particular application.
 32. A light emitting assemblycomprising at least a tray that forms a cavity or recess, at least onelight source positioned within the cavity or recess, at least one film,sheet, plate or substrate positioned over the cavity or recess throughwhich light from the light source is emitted, wherein at least onesurface of the film, sheet, plate or substrate has one or morereflective or refractive surfaces that are well defined optical elementsor deformities for controlling the light output ray angle distributionof the light emitted to suit a particular application.